Josephine Condemi
«We are the heirs of the distressed fish that finds a way to breathe in what would otherwise suffocate it1»: living beings have always sought new ways to survive. More than two billion years ago, when atmospheric hydrogen ran out, bacteria began using water for photosynthesis to nourish themselves. Then, millions of years later, as oxygen—released by that very photosynthesis—filled the air, their descendants started adapting to breathe it, making vital what had once been toxic.
We still carry traces of this history within us: mitochondria, the energy-producing organelles inside our cells, are believed to have originated from anaerobic bacteria that were engulfed in a form of symbiosis and eventually transferred their genetic material to the host cell. Symbiogenesis, random genetic mutation, DNA recombination, and reproduction are just some of the ways in which living systems generate new forms. Constantly exposed to exchanges of matter and energy with their environment, they are continually prompted to “test” their self-organisation. And when they fail to integrate new information into their existing structure, they have two choices: collapse or transform into a new equilibrium, a new configuration. It is a process that the philosopher Whitehead called “the creative activity of nature”2.
The evolutionary creativity of bacteria
The first living beings to inhabit the planet were bacteria, which remained alone for two billion years. «All current forms of life descend from a single clone3» explained biophysicist Harold Morowitz. From that one ancestor emerged a vast and intricate network that, over two billion years, transformed both the atmosphere and the surface of the Earth. As physicist Fritjof Capra noted, during that period bacteria «invented all the biotechnologies essential for life, including fermentation, photosynthesis, nitrogen fixation, respiration, and rotational techniques for rapid movement4» through three strategies of «evolutionary creativity5»: genetic mutations, DNA recombination, and symbiogenesis. Genetic mutations are random errors in DNA self-replication, whereas DNA recombination involves the free exchange of genetic material, up to 15% within 24 hours. One bacterium releases genetic material, another acquires it. Given the speed at which bacteria reproduce, these two strategies are particularly effective in “testing” the best combinations for adaptation and structural coupling6 with the environment.
The third strategy is the evolutionary mechanism of endosymbiosis7, discovered by biologist Lynn Margulis. Bacteria, being life forms without a cell nucleus, can be incorporated into other life forms for mutual survival advantage, eventually transferring their genetic material to the host cell. This mechanism of evolutionary creativity enabled the formation of eukaryotic, i.e. nucleated, cells. These cells emerged through long-term coexistence with bacteria and other organisms, from which they “absorbed” various metabolic functions, proving invaluable for further differentiation and evolution, ultimately leading to plants, animals, and, eventually, us humans. The mitochondria in our cells, the chloroplasts in plant cells, the tail of a sperm cell, and even the rods and cones in the eyes of all vertebrates (humans included) all originated from bacteria.
«The evolution of plants and animals from the microcosm occurred through a succession of symbiotic events, in which bacterial inventions from the preceding two billion years were combined into endless expressions of creativity, selecting life forms that could survive8».
The creative recombination of sex
From bacteria to eukaryotic organisms, then algae, fungi, jellyfish and other marine creatures, followed by molluscs, vertebrates, amphibians, reptiles, angiosperms, mammals, primates, and finally humans: the more complex life forms became, the less they were able to regenerate themselves entirely. While polyps can reconstruct almost their entire body, insects and crabs can regenerate their internal organs. Other animals, including humans, can only renew their tissues before ageing and dying. Creative recombination for the survival of a species thus occurs through sexual reproduction, «the fundamental biological process for maintaining and reproducing identity9».
Margulis and Sagan explained how sexual innovation, that is, meiotic (fusion-based) sex, emerged less than a billion years ago in organisms descended from bacteria, the protoctists, as a response to stress. However, what we call sex is actually the result of many distinct components that came together over the course of evolution: meiosis, the process in which the number of chromosomes in a nucleus is halved to form egg or sperm cells; the fusion of genetic material from these two cells during reproduction, rather than at any time of day as in bacteria; the emergence of differentiated gametes, which were initially nearly identical; the connection between fertilisation and embryo formation, and so on. «Beyond its reproductive function, sex is […] a manifestation of the natural tendency to mix things, to introduce randomness, leading to a loss of discrete identity due to the tendency of material systems to move towards more probable states10» in a transient state of fusion.
«Life exhibits far more variety in the realm of sex, both within and across species, than our narrow view of normality might lead us to believe11» noted Margulis and Sagan.
Take the spotted hyena, for example. Until the 1990s, no one could determine its sex. It was later discovered that what appeared to be a penis was, in fact, an unusually enlarged clitoris, that female hyenas—larger than males—lack a vagina, that they give birth painfully through the urethra, and that they synthesise testosterone in the uterus. «Relative to their own species», concluded Margulis and Sagan, «hyenas are perfectly normal12».
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From transitions to new structures
Between the 1960s and 1970s, Nobel Prize-winning chemist Ilya Prigogine studied Bénard cells—the ordered mosaic of hexagons that forms under specific conditions when a liquid is heated from below. According to the second law of thermodynamics, the universe’s entropy will always increase until it reaches equilibrium (or death). So how do ordered structures like Bénard cells emerge from disorder? Prigogine described how dynamic systems, open to exchanges of matter and energy with their surroundings, are constantly subjected to fluctuations that “test” the molecular configuration they have reached so far. «No system is stable against all transformations13»: in systems far from equilibrium, small changes can trigger substantial modifications, leading to new forms of order—new configurations where matter “self-organises” spontaneously, producing structures better suited to the altered context. Prigogine called them dissipative structures, highlighting how movement and energy dissipation can generate order, usually associated with stillness.
A dynamic system can respond to fluctuations in two ways: through a self-balancing feedback loop (negative feedback), where the existing configuration “resists” change, or through a self-amplifying feedback loop (positive feedback), where instability grows, and the fluctuation spreads throughout the system. The point where the system stands “at a crossroads” between old and new is known as a bifurcation point. In mathematics, dynamic systems are described by nonlinear equations, which, thanks to computational advancements, can now be visualised graphically as trajectory images over time—known as attractors. Some attractors are fixed, meaning the system reaches an equilibrium; others are periodic, where it oscillates regularly. But there are also strange attractors, which never repeat the same pattern.
Strange attractors exhibit fractal geometry: zooming in on a portion of the image reveals the same patterns as a whole. The most complex mathematical structure we know is the Mandelbrot set, named after the mathematician who coined the term “fractal”.
The emergence of new forms from bifurcation points is just one example of the intrinsic creativity of life—one that, in humans, endowed with self-awareness, language, and culture, takes on even richer dimensions and possibilities.
The story this article is about was discovered using an artificial intelligence tool, Asimov, developed by ASC 27, especially for Mangrovia. The tool helped us find the story, but the rest of the content you read and see is the outcome of creative processes and human sensibilities and is in no way generated by artificial intelligence. Follow us to find out the details of how we use artificial intelligence in the newsroom!
- Morin E. (2004), Il metodo 2. La vita della vita, Milano: Raffaello Cortina, p. 270 ↩︎
- Whitehead A. N. (1920). “Time”. Chapter 3 in The Concept of Nature. Cambridge: Cambridge University Press: 49-73. ↩︎
- Morowitz H. (1992), Beginnings of cellular life, New Haven: Yale University Press, p. 88 ↩︎
- Capra F. (1996), The web of life, New York: Anchor Books, p.228 ↩︎
- Capra F. (2004), La scienza della vita, Milano: Rizzoli, p. 62 ↩︎
- Maturana H., Varela F. (1987), L’albero della conoscenza, Milano: Garzanti ↩︎
- Margulis, L. (1970), Origin of Eukaryotic Cells, New Haven: Yale University Press ↩︎
- Capra F. (1996), op.cit., p. 245 ↩︎
- Margulis L. e Sagan D. (1998), What is sex?, Simon & Schuster ↩︎
- Ibidem ↩︎
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- Ibidem ↩︎
- Prigogine I. e Stengers I. (1981), La nuova alleanza, Torino: Einaudi, p.171 ↩︎
